College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China.
Small. 2022 Apr;18(17):e2107387. doi: 10.1002/smll.202107387. Epub 2022 Mar 24.
Platinum (Pt), as a commonly used electrocatalyst in direct methanol fuel cells (DMFCs), suffers from sluggish kinetics of both the methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). Geometric engineering has been proven effective for improving the MOR and ORR activities. Thus, by modulating the Pt precursor and poly(vinylpyrrolidone) (PVP) dosages, different porous PtCu nanotubes constructed by hollow nanospheres, solid alloy, and Pt-rich skinned nanoparticles, respectively, are successfully synthesized. Among them, the solid PtCu alloy nanoparticle coherent nanotubes exhibit the specific activity 9.42 times higher than Pt/C toward MOR, while the hollow PtCu alloy nanosphere coherent nanotubes show the specific activity 4.85 times higher than Pt/C toward ORR. The different Pt:Cu ratios of hollow nanospheres, solid alloy, and Pt-rich skinned nanoparticles cause the differences in electron transfer from Cu to Pt as well as electronic structures of Pt. As a result, the binding energies of intermediates can be regulated, leading to the enhancement in MOR and ORR.
铂（Pt）作为直接甲醇燃料电池（DMFCs）中常用的电催化剂，其甲醇氧化反应（MOR）和氧还原反应（ORR）的动力学都较为缓慢。几何工程已被证明可以有效提高 MOR 和 ORR 的活性。因此，通过调节 Pt 前体和聚（N-乙烯基吡咯烷酮）（PVP）的用量，可以分别成功合成由空心纳米球、固溶体合金和富 Pt 皮的纳米颗粒构建的不同多孔 PtCu 纳米管。其中，固溶体 PtCu 合金纳米粒子连贯纳米管对 MOR 的比活性是 Pt/C 的 9.42 倍，而空心 PtCu 合金纳米球连贯纳米管对 ORR 的比活性是 Pt/C 的 4.85 倍。空心纳米球、固溶体合金和富 Pt 皮的纳米颗粒的不同 Pt:Cu 比导致电子从 Cu 转移到 Pt 以及 Pt 的电子结构的差异。因此，可以调节中间体的结合能，从而提高 MOR 和 ORR。
